Make sure the virtual has a mailbox. We usually set the virtual to cf/b/na to inmail, then place an in skin button (77) on a button of a phone. When a message is sent to the virtual mailbox, the in skin button flashes. Just press it to retrieve the message. We label it a general mail box button.
Or, you can make the virtual a group mailbox, cf/b/na to vm, send it to a routing box, in 47-11 default mailbox set it as station, and place the mailbox number there. That could be any station mailbox, not just a virtual.